I disagree. For a small to medium size site, getting 99.99% uptime should basically be the default. If you have a competent staff and a decent provider, about the only thing that will take you down is a power/equipment failure at the DC - which does happen, from time to time, admittedly. Yeah, Rackspace had some problems this year, but most of the other tier 1 hosts have been rock solid.
Obviously it's more complex for a large site but for the vast majority I would say that level of uptime is the rule rather than the exception.
Three nines is pretty unacceptable in this day and age. Providers might only guarantee that level of uptime but if they really were down that much I'd run a mile. Netcraft is your friend!
How are you defining a site and uptime? Are you talking about dynamically switching systems to allow for upgrades without downtime?
I'm mostly wondering how it compares with the setup at my current location.
I have worked on systems that were designed for this, but I'm not sure if it's cost effective for most web applications. Most things can wait on occasion.
and what happens when an engineering fluke hits your KV store and locks it up. And it takes you 10hours to fix :)
You see your not actually paying for the 3 9's or the 5 9's. That is just corporate bullshit. Your paying for the promise that whatever the problem someone will be able to fix it in a few hours at most.
Obviously it's more complex for a large site but for the vast majority I would say that level of uptime is the rule rather than the exception.
Three nines is pretty unacceptable in this day and age. Providers might only guarantee that level of uptime but if they really were down that much I'd run a mile. Netcraft is your friend!
update: edited post to better reflect reality